Phase formation regularities in Fe-based nanometer powders prepared by gas evaporation process

摘要

A serials of Fe based nanometer powders were fabricated by reduced pressure gas evaporation process with induction current as the heating source. The formation regularities of the phases in as prepared powders and the structures of the nanometer particles were investigated. Pure Fe nanometer powders with about 70% γ Fe phase is prepared in present study by using the powder collector with good cooling effect. In the nanometer powders of Fe Ni alloy, solid solution phase γ (Fe,Ni) and α Fe phase form, but for Fe Cr alloys only solid solution phase α (Fe,Cr) forms. In the nanometer powders of Fe Cu alloy, only pure metal phases of γ Fe and Cu form, and no compound or solid solution phase exists. The formation regularity of the phases in the nanometer powders of alloys obeys the common phase laws in bulk alloy state.